cogmaster_ep2bis
TRANSCRIPT
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EP2. Social learning
Elena Pasquinelli
Education, cognition, cerveauCogmaster 2010-2011
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• Kinds of knowledge/kinds of learning– An introduction to some basic learning mechanisms,
in particular social learning• NP: in short– Why is it interesting?
• Broadening the view on cognition (social cognition)
• A practical example of social issues in education– 1:1 tutoring
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A STEP BACK TO EARLY LEARNING MECHANISMS:- STATISTICAL LEARNING
- IMPLICIT LEARNING- EXPLANATORY LEARNING
- LEARNING BY ANALOGY
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Learning = the modification of behavior in light of experience
• statistical learning, • learning by imitation, • explanation-based or
causal learning • and learning by analogy. • Using these simple
learning mechanisms, the brain appears to build up complex representations about how the world is.” (Goswami, 2008, p. 52)
• Under this definition, learning is a common function to different animal species
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Statistical learning
• “Babies appear to be able to make connections between events that are reliably associated, even while in the womb.
• Once outside the womb, they appear to be able to track statistical dependencies in the world, such as conditional probabilities between visual events or between sounds. This turns out to be a very powerful learning mechanism.” (Goswami, 2006)
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Statistical learning and language• Critical periods in language
learning differ in the three aspects of language: phonetics (before 12 months), syntax (18-36), lexicon (forever)
• Why are children better than adults?
• (Kuhl, 2004): neural commitment– Once perceptual systems are
committed they filter new information
– Commitment is done between 6 and 12 months (for phonetics): before, children distinguish all the phonetic units of all languages
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Statistical learning and language
• How can children succeed in a difficult task as identifying and grouping the more or less 40 phonemes that compose their language? In the middle of a great variability of speech? (Kuhl, 2004)
• Language acquisition has provoked a debate on nature (Chomsky) vs nurture (Skinner)
• Statistical learning (Saffran, et al, 1996) applies to the capacity to identify phonemes and to the capacity of segmenting words– Japanese and English infants are both exposed to both /r/ and
/l/ sounds, but in Japanese the sound /r/ is much more frequent – Babies spot the transitional probabilities between syllables
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Implicit learning• Implicit learning theories are based
on the capacity of extracting regularities, e.g. on grammar:– Reber, 1967, 1989: implicit learning
allows the acquisition of complex, abstract knowledge without awareness and effort (extraction of abstract rules)
– Pacton & Perruchet, 2006: acquisition of the aptitude to correctly answering to certain situations, without the intention of learning (no extraction of abstract rules; the learning of rules requires explicit learning)
• the crucial variable is the exposition to regularities in the environment
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Implicit learning of errors
• If implicit learning can happen by repeated exposition (with attention), then the repeated exposition to errors favors the learning of errors
• Multiple choice tests enhance learning of good, and bad, answers (Marsh, et al., 2007, p. 195)
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• It does not mean one can learn without attention (concurrent attentional tasks lower the capacity of implicit learning)
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Statistical learning & Extraction of causal structures
• “… specific perceptual features of two objects in a “launching” event (where object A impacts object B, causing it to begin to move) may vary, but spatio-temporal dynamics (and therefore causal structure, i.e., the fact that A causes B to move) will vary less. (Goswami, 2008b, p. 9)
The perceptual “illusion” of causality during launching and other visual events noted by Michotte (1963)
http://cogweb.ucla.edu/Discourse/Narrative/michotte-demo.swf
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Learning by explanation & analogy
• “In the field of machine learning, explanation-based learning depends on constructing causal explanations for phenomena on the basis of specific training examples, using prior domain knowledge.
• If infants were merely learning condition-outcome relations, as in associative learning, then they would be unable to make predictions about novel events.” (Goswami, 2008, p. 66)
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Learning by analogy
• “In learning by analogy, “we face a situation, we recall a similar situation, we match them up, we reason, and we learn” (Winston, 1980). We may decide whether a dog has a heart by thinking about whether people have hearts (young children use “personification analogies” to learn about biological kinds, see Inagaki & Hatano, 1988), or we may solve a mathematical problem about the interaction of forces by using an analogy to a tug-of-war (young children use familiar physical systems to reason about unfamiliar ones, see Pauen, 1996).
• (Goswami, 2008)
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SOCIAL LEARNING MECHANISMS:- STATISTICAL LEARNING IS NOT ENOUGH- IMITATION AND OTHER SOCIAL LEARNING MECHANISMS
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Language: statistical learning is not enough
• Statistical learning can have strong and durable effects on phonetics at 9 months of age, and with short-time exposure to statistical regularities – 9 months old children can learn to
distinguish Mandarin phonemes from exposure to play and interaction with a Mandarin speaking tutor
• But is statistical learning enough? – 9 months old children cannot learn
to distinguish Mandarin phonemes from a Mandarin speaking TV-canned /audiotaped tutor
• Social interaction is required
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Social interaction
• Social interaction can have an effect on learning through:– Enhancement of attention– Additional information
(gaze to object)– Activation of mirror
systems, and other mechanisms for perception-action linking in the brain
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Implicit learning is not enough• Perruchet & Pacton, 2006: Explicit
learning completes implicit learning with rules
• Perruchet & Pacton, 2006: In any case, explicit learning raises performances in comparison with implicit learning (school instruction demands more than above chance performances)
• Reber, 1989: introduction of explicit instruction is especially useful when information is provided before (rather than during or after the implicit learning phase), maybe because it helps directing attention on meaningful aspects
Bransford, Brown, & Cocking, 2000: Judd & Scholckow 1908’s experiment confirms that explicit instruction (before training) enhances performances for new situations
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Imitation
• “Learning by imitation can be defined as B learns from A some part of the form of a behavior…
• One example is learning the use of a novel tool by imitating the actions of another user with that tool. (Goswami, 2008, p. 62-63)
•Learning by imitation is present in the human baby by the age of at least 9 months (Meltzoff, 1988)•At 14 months, babies imitate with a delay (1 week) and rationally:• They imitate certain features of the
action if and only if they consider that they are functional to the reaching of the goal, not if they are contingent to the situation• (Meltzoff, 2005)• (Gergely, et al., 2002)
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Imitation -> mind reading• The like-me hypothesis states
that infants grow to understand others in three stages:
• Imitation: babies come to understand (or experience) the intrinsic connection between observed and executed acts, as manifest by newborn imitation
• First-person experience: Infants experience the regular relationship between their own acts and underlying mental states.
• Understanding Other Minds: Others who act "like me" have internal states "like me.” – (Meltzoff, 2005)
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Imitation, social cognition & mirror neurons
• Among the studies on social cognition, mirror neurons have gained lot of attention
• Mirror neurons are involved in the representation of an action
• Mirror neurons are activated when observing an action, independently from the specific motor realization of the action
• Mirror neurons are related to the goal, and the agent
• Mirror neurons could be involved in the understanding of others’ intentions and to imitation
• Speculatively, in empathy (Iacoboni, et al., 2005)
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Learning by imitation & TV• 14 months’ babies can learn the same
actions from real experimenters and from experimenters canned in a TV video (on live)
• But they learn less than from live action (video deficit effect) (Zack, et al. 2009, p. 14)
• Is that because of 2D/3D encoding differences? What happens with 3D models? – the limit comes from the transfer of
information from one dimension to another– Infants do just as well imitating 2D/2D than
3D/3D: 2D is not as impoverished as to block imitation, and 2D does not represent a poorly understood condition in comparison with 3D
– Representational flexibility seems to be the problem
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Mind reading -> Imitation
• Infants understand and imitate adults’ intentions, not only their behaviors
• Learning by imitation seems to require the understanding of others’ intentions (Tomasello, 1990)
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Understanding human intentions• Three levels of understanding
others’ actions & reading of intentions)– Perceiving others as actors
that produce their actions (6 months old children)
– Perceiving others as having goals for their actions (9 months)
– Perceiving others as making plans for reaching their goal, and choosing the most rational action (14 months)
(Tomasello, et al. 2005)
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(Motivation for) Engaging in shared intentions
• 3 levels of engagement in shared intentions:– Dyadic engagement: face to
face interactions and protoconversations with shared emotions
– Tryadic engagement: doing things together, but without assigning roles for the reaching of the goal; sharing perception and goals (9-12 months)
– Collaborative engagement = sharing action plans (12-15 months)
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Humanness• At the origin of human culture
and cognition stand two capacities:
• - mind reading, and in particular: the capacity of perceiving and understanding others’ intentions
• - a motivation for engaging in shared intention activities
• So: shared intentionality is what makes humans special in the animal reign
• (Tomasello, 2005)
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Cultural intelligence hypothesis• Baby humans differ from
primates mainly because of social abilities– Further differences between
humans and primate might derive from these social-cultural
– Humans have developed special cognitive skills as a result of the development of specialized skills for absorbing knowledge and practices of their social group• Herrmann, et al., 2005
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NATURAL PEDAGOGY: - THE INDUCTION PROBLEM- THE CONDITIONS FOR NATURAL PEDAGOGY
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Induction problem
• Induction problem: how to compose bits of episodic information into a general knowledge that can then be applied to several, different situations
• Learning generalizable knowledge from social interactions seems to be specific to humans
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Natural pedagogy
• Natural pedagogy =– Social learning mechanisms (present in different species)+– A special form of communication (human-specific)
Double function: reception/production
• Natural pedagogy seems to be universal, thus “natural”
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Social learning mechanisms
• Social learning mechanisms are common to several animal species
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Special form of communication
• Development of tools’ making practices represents an evolutive pressure– Because these practices cannot be learned/transmitted by other, available
mechanisms of learning from imitation/observation*– Because they represent opaque contents for cognition
• Thus, humans have evolved mechanisms that serve the pedagogical function of transmitting cognitively opaque contents
• These mechanisms are part of the more general communication system, but not the same system that serves episodic communication, as it can be found in different species– They consist of demonstration acts: ostensive-referential demonstrations
• Communication has evolved not only for collaboration-purposes but also under the pressure of learning/teaching purposes
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Adults/children natural pedagogical system
1. Children observe and imitate adults– Children spontaneously imitate causal actions that lead to achieve goals, and
ignore other components of the global action– The others components of the action are opaque to children’s cognition– But, when the “teacher” makes it clear that these components of the action
are relevant, children do pay attention, and imitate
2. Adults use their communication system to facilitate children’s learning/Young children are receptive to adult’s ostensive demonstration before they are able to use it for learning
• Ostensive signals allow to– Disambiguate the nature of the action (communication, not just using the
tool)– Disambiguate the target of the communication (you)
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Ostensive signals• 1. preferential
attention for the sources of ostensive signals
• Preference for ostensive signals :– Gaze contact
• Newborns preferentially look at schematic face-like patterns with direct gaze vs averted gaze; preference disappears when faces are upside-down; preference disappears when the typical iris/sclera patters of eyes is inverted
• Same neural activation for infants and adults in response to direct gaze and common neural activation for two different ostensive stimuli (direct gaze & eye-brow raise)
– Motherese– Motionese
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Referential expectations• 2. Referential
expectation induced by ostensive contexts
– Infants follow the gaze of interacting adults to identify what they are looking at, before they can understand language
– Useful for sampling parts of the world that others found interesting, and present in other animals
– Human infants follow gaze shifts only when these are preceded by ostensive signals (greeting, gaze contact)
– Infants expect to find an object at the “end” of a gaze-following in an ostensive context– 13 months old Infants expect to find
the named object (if its name is part of their vocabulary)
– But not if the gesture and word are emitted by different persons
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Interpretation bias• 3. interpretation bias to
preferentially encode the content of ostensive-referential communication as representing generalizable knowledge”
– Not only infants are prepared to receive ostensive–referential communication, but they do expect to learn something generalizable from it (and not just a particular instance) = to learn about referent kinds– When infants (18 months old) observe adults expressing
emotional valence in relationship to an object in a non-communicative context, they infer that person’s particular preference (she does not like it). But when the same pattern of valence expression is inserted in a communicative context, infants attach the expressed value to the object and expect that other people will react in the same manner to the object (it is disgusting for everybody)
– Infants (9 months old) shift their encoding pattern from location to appearance features when the situation shifts from non-communicative to communicative.– They are more likely to detect change in location in a
non-communicative situation, but detect more often features change in a communicative situation and neglect location; and this happens even in situations in which location is important, pragmatically, such as hiding games
– This bias could explain A not-B task errors: children stop being interested in location and do not mind about the new location, because the communicative contexts has made them focus on the features of the object. In fact, once communicative cues are removed, the errors diminish.
– Appearance features are better candidates for later use and object identification, thus for generalization.
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• “Child development is today conceptualized as an essentially social process, based on incremental knowledge acquisition driven by cultural experience and social context. We have “social” brains.” (Goswami, 2008b, p. 1)
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LEVELS OF ANALYSIS
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Distributed cognition• The unit of analysis
of cognitive performances should be extended beyond the individual so as to encompass social and material interactions with tools– (Hutchins, 1995)
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Extended cognition• Performances typically
described as cognitive are significantly worst in absence of interaction with tools, others, or of epistemic actions that have no other aim than favoring a better knowledge of the world– (Clark & Chalmers,
1998)
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Social neuroscience“… the brain does not exist in isolation but rather is a fundamental but interacting component of a developing or aging individual who is a mere actor in the larger theater of life. This theater is undeniably social, beginning with prenatal care, mother-infant attachment, and early childhood experiences, and ending with loneliness or social support and with familiar or societal decisions about care for the elderly. … Social psychology, with its panoramic focus on the effects of human association and the impact of society on the individual, is therefore a fundamental although sometimes unaknowledged complement to the neurosciences.” (Cacioppo & Berentson, 1992, p. 1020)
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Integration of levels of analysis
importance of multilevel, integrative analysis of complex psychological phenomena
1. Neurochemical events influence social processes/Social processes influence neurochemical events
• Difficulty in the integration of neuroscience and social psychology levels of analysis: different scales into which brain and behavior can be represented
• The level of organization of psychological phenomena vary from molecular the organism set into a physical environment and a socio-cultural context
• Neurosciences generally encompass the lower level of the spectrum, social psychology the higher one
• Integration means that analyses at each level of organization can inform, refine or constrain inferences in the other levels
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2. The study of the elements of the system can fall short of useful and comprehensive explanations• In other sciences, the
existence of different levels of explanation (protons/rocks) does not lead to considering geology as a folk theory when compared with molecular level models.
• Distinctive levels of analysis are complementary, not alternative
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3. A set of neural events can be a sufficient cause for producing a psychological phenomenon, without being a necessary one• E.g., lying rubustly produces
certain electrodermal responses ; but other conditions can produce the same electrodermal responses
• In the case of multiple determinants of a certain behavior, studies on the sufficiency of a certain neurophysiological condition in causing a certain phenomenological phenomenon are impôrtant but lack generalizing power.
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from medicine to education• “… no single level of behavioral organization is
best for all psychological questions.• An example can be found in the relative utility
of specifying the sociocognitive versus the neurophysiological basis of patient delay following the onset of gynecologic cancer. Women can now survive most gynecologic cancers if the disease is diagnosed and treated early. … The form of the representation of patient delay offered by neuroscientific analyses of patient delay, although perhaps contributing to more complete understanding of the phenomenon, is not optimal for identifying the determinants of patient delay or for developing effective interventions to minimize such delay. Huge savings in resources and human suffering are there to be reaped not through a specification of the brain circuits underlying patient delay, but by well-conceived public health campaings that identify the early signs of cancer… ” (Cacioppo & Berentson, 1992, p. 1022)
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Affective neuroscience• Importance of
emotions for rationality
• Role of motivation in learning
• Role of reward and punishment– (Posner & Rothbart,
2008; Immordinao-Yang, 2010)
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EXAMPLES & ISSUES OF SOCIAL LEARNING-TUTORING
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The 2 sigma problem• Bloom, 1984 has compared 3 conditions of instruction:
– Conventional (1:30, periodic tests for marking)– Mastery learning (1:30, formative tests for measuring mastery & immediate feedback)– Tutoring (1:1 or 1:2 1:3, formative tests and feedback)
• He found that the average student under tutoring was above 98% of the students in the control class = 2 standard deviations above the average of the control class
• The average student under mastery learning was about 1 standard deviation above the average of the control class (above 84% of the students in the control class)
• 90% of the tutored students and 70% of the mastery learning students attained levels of achievement that only 20% of the students in the control class had achieved– Tutoring would probably not enable the top 20% of traditional instruction group
students to do better; but 80% of traditional classrooms do poorly in comparison to tutoring
– Maybe this is because teachers direct their attention to some students, and ignore others